(a) Field of the Invention
The present invention relates to a method for preparing an anti-microbial or anti-coagulating polymer resin, particularly to a method for preparing a functional polymer resin that can prevent secondary bacterial infection, inhibit coagulation of blood when inserted into a human body, and maintain superior medicinal efficacy durability even after injection and extrusion molding, by combining a material that is safe to a human body, has superior compatibility with materials for commonly used medical instruments/appliances, and has superior anti-microbial or anti-coagulating properties on the surface of a product, with various materials for medical instruments/appliances such as silicon, etc., in a non-solvent form.
(b) Description of the Related Art
Various forms of organic anti-microbial formulations for conventional anti-microbial and anti-pollutant functions such as quaternary ammonium salt, chlorohexidine, carbendazim, thiazole, azole, Sn types, etc. have been reported. However, many of the anti-microbial and anti-pollutant products using the above materials have problems including unsecured safety due to toxicity, and ecosystem destruction due to release of environmental hormones. Additionally, their anti-microbial effects may be decreased due to thermal decomposition during high temperature processing, and product deterioration due to yellowing may also occur. Particularly, a polymer resin used in the medical field such as for an artificial blood vessel, an artificial heart, an artificial bone, artificial skin, etc. should be secured safety to a human body, and they should be protected from various pathogenic bacteria. However, anti-microbial materials of the prior art cannot completely satisfy these requirements.
Conventional technologies for inhibiting bacterial infection of medical instruments/appliances have been disclosed in various publications. As examples, U.S. Pat. No. 6,342,250 has disclosed a technology for coating a pharmaceutically active material on a polymer surface; U.S. Pat. No. 5,019,283 has disclosed a technology for coating a pharmaceutically active material selected from Ag and an anti-microbial composition on a polymer surface; and U.S. Pat. No. 5,902,283 has disclosed a technology for coating a pharmaceutically active material such as rifamycin, penicillin, ciprofloxacine, etc. on the surface of a catheter.
According to the above-mentioned conventional technologies, an anti-microbial material is coated on a surface by an additional process after preparing a product, and drugs are eluted by DDS (Drug Delivery System) to exhibit surface anti-microbial efficacy. However, they have disadvantages including process workability, durability and effect durability, toxic problems due to remaining materials that are excessively eluted in the body, and formation of volatile organic compounds (V.O.C) due to the use of an organic solvent for coating.
In addition, when medical instruments/appliances are inserted into a human body, they react in the following way with blood to cause blood coagulation. Firstly, plasma proteins such as fibrinogen, albumin gamma-globulin, etc. are absorbed into the medical instruments/appliances. After a protein such as fibrinogen, which causes formation of thromboses, is absorbed, adhesion of blood platelets begins to cause more adhesion and coagulation of blood platelets to form thromboses. Simultaneously, a blood coagulation system is operated as blood coagulation factors are activated, and finally thrombin activates fibrinogen into fibrin to coagulate fibrin, thereby generating blood coagulation.
In order to solve these blood coagulation problems, studies on technologies for preventing blood coagulation by medical instruments/appliances (e.g., catheters, stents, artificial bone, artificial articulation) are under progress. As examples, as a method for preventing formation of thromboses by inhibiting adhesion of blood platelets, a method of using albumin is known (M A Packham, G Evans, M F Glynn, and J F Mustard, The effects of plasma proteins on the interaction of platelet with glass surfaces, J. Lab. Clin, Med., 73: 686-97,1969; GH Ryu. Dk Han, YH Kim, and BG Min, Albumin immobilized polyurethane and its blood compatibility, Trans. Am. Soc. Artif. Int. Organs, 38: 644-648, 1992). Additionally, as a method for inhibiting formation of thromboses by inactivation of a coagulation factor, a method of combining heparin anticoagulant with a living body material is disclosed in EP 0 294 905 1A; and a method of treating heparin and polyethyleneoxide together is disclosed in EP 0081 853 1A. However, since these methods also use coating of anti-coagulants on an external surface, they cannot overcome the above-mentioned disadvantages of conventional bacterial infection inhibition technologies.